The present invention relates to a device for automatically sorting elements, such as caps, and feeding the elements to a discharge point in a specific orientation.
Apparatus for sorting articles from a mixed mass of articles on an inclined rotating surface and arranging the articles in single file for discharge, is available in the art. Apparatus of this sort, also referred to as orbital selecting or sorting devices, utilize centrifugal force to transfer the articles on the rotating surface to the perimeter of the surface for selecting or sorting.
The apparatus described in Glaude, U.S. Pat. No. 2,388,405, allows selection based on the orientation of open-ended hollow caps. In this apparatus, selection is performed by a stationary member that, in essence, pulls properly oriented caps off of the rotating surface and into the discharge chute. In this device, the selection process must occur at the lowest point on the incline device so that the parts or the elements may be fed off of the rotating surface.
One problem with the orbital sorting devices of the prior art is the feeding speed of the devices has been limited to a maximum of about 1100 parts per minute. Devices that attempt to properly orient the elements to be sorted prior to entry into the discharge chute typically have the lowest feed rate. Apparatus such as in Glaude allow higher feed rates by discarding the improperly oriented parts and feeding only the properly oriented parts. There is a need for an orbital sorting device that produces a high feed rate of properly oriented parts to the discharge chute, with virtually 100% accuracy.
A device described in Applicants' co-pending utility application, Ser. No. 101,853, uses an optical sensor to sense the orientation of caps at the periphery of a rotating disk. An airjet is triggered by a signal from the optical sensor to eject improperly oriented caps back into working surface of the disk. Applicants' prior device allows very high feed rates, exceeding 3000 parts per minute, at a very high orientation accuracy. The device described in Applicants' Ser. No. 101,853 is a high-speed device, but an apparatus is still not available that combines high feed rates with virtual 100% accuracy.
Some devices of the prior art have employed a starwheel or a pinwheel to sort properly oriented caps. In devices of this type, high sorting accuracy is achieved by having arms of a rotating starwheel enter the open end of a cap, or strike the closed end of the cap, depending on the cap orientation. In the patent to Shenoha, U.S. Pat. No. 3,570,642, a rotating pinwheel is situated in an exit chute. The pinwheel pins engage the open end of properly oriented caps to restrain them against ejection by a striker bar. Apparatus described in Belada, U.S. Pat. No. 2,270,713, and Eddy, U.S. Pat. No. 3,811,551 use a pair of starwheels to extract an improperly oriented cap from on section of an exit chute. None of these devices employ a starwheel to select parts on a rotating disk. Other key differences will be made apparent by the following description.
It is an object of the present invention to provide an apparatus that is capable of high feed rates in an orbital sorting device and that is as infallible as possible in feeding only properly oriented elements. Further objects and benefits of the present invention will be apparent from the ensuing description and accompanying figures.